The Library is a building in the island where players can earn rewards for completing Monster Collections called Books. Each Book contains Chapters.
Players can earn rewards like food, gold, runes, monster cells and Joker cells like Nebula, Mythic Amber, Stardust, Ambrosia and Elementium for completing the Chapters.

The Library unlocks at level 12.  

  • Monsters must be hatched and placed in a habitat/vault to appear in the Library. Ranked up collections of the same Monster requires having these Monsters ranked up.